In recent years, vehicles in which fuel cells using hydrogen gas are employed as a source of power have been put in practical use. In this type of vehicle, the hydrogen gas must be supplied at a hydrogen gas supply station or the like, which is similar to a filling station for regular gasoline vehicles. In this case, the hydrogen gas is supplied by connecting a pipe coupling member attached to an outlet of a hose for discharging and supplying hydrogen gas from a hydrogen gas storage tank provided on the supply station side to a pipe coupling member attached to an inlet of a hydrogen gas storage tank on the vehicle side (Japanese Unexamined Patent Application No. 2004-293568).